Have PySide2 fixhdr handle arbitrary tracedb size when list time corrections window requested

OS: Fedora 36.

Trace db size: 19 GB in 8556 files.

Current behavior: I set time tag to questionable with 0.0 s correction (recommended procedure). Applying time correction went normally. I then requested a List Time Corrections. The window came up and displayed some list time correction information, but the scroll bar appeared too short for all time blocks to be listed in the window. I also received a popup message (from OS) that fixhdr is not responding. I left the List Time Corrections Window up for approximately 90 minutes.

Solution: I am not sure what is causing the List Time Corrections window to display fewer time blocks than are present in the selected traces, perhaps pagination over a certain number of time blocks would let all blocks be viewed? A "Listing Time Corrections, please wait" window may remove the problem of the OS sending a message about the program not responding.

Other information: Another installation of fixhdr (2022.1.0.0) on the same machine can bring up the List Time Corrections Window as expected: it populates fully after examining all selected files and the program responds normally (does not become unresponsive).